Average diesel prices in the United States have climbed to a new record, the motorists’ association AAA says, as damage to Gulf refineries during the war against Iran disrupted supplies, AFP reports.

The price of the fuel largely used in road hauling, agriculture and construction hit $5.9015, the AAA said, around 30 cents higher than the average just one week earlier.

Diesel cost just $3.71 on average a year ago, and the higher prices are squeezing farmers and truckers, which could be forced to pass on the increases to consumers.

Average prices for regulator gasoline stood at $4.15 a gallon on Monday — when millions of Americans typically travel by car for the Labour Day holiday.

That is up from $3.20 on average a year ago. In western US states, prices are even higher, with regular gas costing $5.86 in California and $4.54 in Arizona, the AAA said.